Chlorotrimethylsilane

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

No data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to an appropriate OECD test guideline, with acceptable restrictions. The restrictions were limited reporting of test substance information, and animal experimental conditions.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1982

Report date:

1982

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

GLP compliance:

not specified

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Chlorotrimethylsilane

EC Number:

200-900-5

EC Name:

Chlorotrimethylsilane

Cas Number:

75-77-4

Molecular formula:

C3H9ClSi

IUPAC Name:

chloro(trimethyl)silane

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

Hilltop-Wistar albino rats weighed between 200 and 300 g.
TEST ANIMALS
- Source: No data
- Age at study initiation: No data
- Weight at study initiation: 200-300 g
- Fasting period before study: overnight
- Housing: No data
- Diet (e.g. ad libitum): Ad libitum
- Water (e.g. ad libitum): Ad libitum
- Acclimation period: No data


ENVIRONMENTAL CONDITIONS
- Temperature (°C): No data
- Humidity (%): No data
- Air changes (per hr): No data
- Photoperiod (hrs dark / hrs light): No data


IN-LIFE DATES: No data

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: Silicone L-45 oil

Details on oral exposure:

Hilltop-Wistar albino rats received the test material neat or as a 25% dilution (v/v) in Silicone L-45 Oil by stomach intubation with a ball-end stainless steel needle.  

Doses:

Males: 8.0, 4.0, and 2.0 mL/kg; Females: 8.0, 5.7, and 4.0 mL/kg

No. of animals per sex per dose:

5/sex/dose

Control animals:

no

Details on study design:

Animal weights were recorded at 0 days (before dose), 7 days and 14 days (just prior to sacrifice).  At death or sacrifice, each animal was subjected to gross pathologic evaluation. 
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Weighing on Day 0 (before dosing), 7 days and 14 days (prior to sacrifice)
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, gross pathological evaluation

Statistics:

LD50 values were calculated by the moving average method (Thompson, 1947) and were based on a 14-day observation period.

Results and discussion

Effect levels

Effect levels 1

Sex:

male

Dose descriptor:

LD50

Effect level:

< 0.25 mL/kg bw

Based on:

test mat.

Remarks on result:

other: Neat

Effect levels 2

Sex:

male

Dose descriptor:

LD50

Effect level:

5.66 mL/kg bw

Remarks on result:

other: 25% solution in silicone L-45 oil

Effect levels 3

Sex:

female

Dose descriptor:

LD50

Effect level:

6.63 mL/kg bw

Remarks on result:

other: 25% solution in silicone L-45 oil

Mortality:

All male animals died when administered with neat test substance. Females were notadministered the neat test material, based on effects on males.
Males: 5/5, 0/5, and 1/5 at 8.0, 4.0, and 2.0 mL/kg, respectively
Females: 5/5, 0/5, and 0/5 at 8.0, 5.7, and 4.0 mL/kg, respectively

Clinical signs:

other: MALES: Dosage: 8.0 ml/kg Signs of Toxicity: Sluggishness at 2 min; dyspnea and rales in 2 at 2 min; prostration at 15 min; death of 4 at 30 to 45 min. Dosage: 4.0 ml/kg Signs of Toxicity: Fur yellow, ruffled, greasy in texture at 1 day. Normal app

Gross pathology:

MALES:
Dosage: 8.0 ml/kg
Gross Pathology: Stomachs filled with black solid material, white vapor released when cut; livers blanched, tan; spleens enlarged.

Dosage: 4.0 ml/kg
Gross Pathology: Nothing remarkable

Dosage: 2.0 ml/kg
Gross Pathology: In victim, lungs dark red; red fluid in thoracic cavity; intestines red. In surivors, nothing remarkable.

FEMALE
Gross Pathology: Lungs of 1 red and black, vapor released when thoracic cavity cut; lungs of 1 with dark patches, red fluid in thoracic cavity; stomachs filled with black solid material, vapor released when cut; livers blanched, tan.

Dosage: 5.7 ml/kg
Gross Pathology: Nothing remarkable

Dosage: 4.0 ml/kg
Gross Pathology: Nothing remarkable

Applicant's summary and conclusion

Interpretation of results:

harmful

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

In a well-reported acute oral toxicity study conducted using a protocol similar to the now deleted OECD test guideline 401 (of unknown GLP status), the LD50 was 5.66 ml/kg (in a 25% (v/v) dilution in Silicone L-45 oil) for males, and 6.63 ml/kg (in a 25% (v/v) dilution in Silicone L-45 oil) for females. For neat test substance, the LD50 was <0.25 ml/kg, equivalent to <214 mg/kg for males.

Executive summary:

In a well-reported acute oral toxicity study conducted using a protocol similar to the now deleted OECD test guideline 401 (of unknown GLP status), male Wistar rats were dosed with 0.25 ml/kg undiluted Organochlorosilane A-161 by oral gavage. All of these animals died within six days and autopsy showed features consistent with severe irritant and ulcerogenic effects on the alimentary tract. These findings indicated a high degree of acute oral toxicity, and therefore the study was not conducted in females. A 25% dilution in Silicone L-45 oil was significantly less toxic, and LD50s for males and females were 5.66 and 6.63 ml/kg, respectively. Signs of toxicity included sluggishness, breathing difficulty and prostration. Gross pathology in the victoms revealed discoloured organs, fluid in the thoracic cavities and black solid in the stomachs.